// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_GFX_GPU_MEMORY_BUFFER_H_
#define UI_GFX_GPU_MEMORY_BUFFER_H_

#include <stddef.h>
#include <stdint.h>

#include "base/memory/shared_memory.h"
#include "base/trace_event/memory_dump_manager.h"
#include "build/build_config.h"
#include "ui/gfx/buffer_types.h"
#include "ui/gfx/generic_shared_memory_id.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/gfx/gfx_export.h"

#if defined(USE_OZONE)
#include "ui/gfx/native_pixmap_handle_ozone.h"
#elif defined(OS_MACOSX)
#include "ui/gfx/mac/io_surface.h"
#endif

extern "C" typedef struct _ClientBuffer* ClientBuffer;

namespace gfx {

enum GpuMemoryBufferType {
    EMPTY_BUFFER,
    SHARED_MEMORY_BUFFER,
    IO_SURFACE_BUFFER,
    SURFACE_TEXTURE_BUFFER,
    OZONE_NATIVE_PIXMAP,
    GPU_MEMORY_BUFFER_TYPE_LAST = OZONE_NATIVE_PIXMAP
};

using GpuMemoryBufferId = GenericSharedMemoryId;

struct GFX_EXPORT GpuMemoryBufferHandle {
    GpuMemoryBufferHandle();
    ~GpuMemoryBufferHandle();
    bool is_null() const { return type == EMPTY_BUFFER; }
    GpuMemoryBufferType type;
    GpuMemoryBufferId id;
    base::SharedMemoryHandle handle;
    uint32_t offset;
    int32_t stride;
#if defined(USE_OZONE)
    NativePixmapHandle native_pixmap_handle;
#elif defined(OS_MACOSX)
    ScopedRefCountedIOSurfaceMachPort mach_port;
#endif
};

base::trace_event::MemoryAllocatorDumpGuid GFX_EXPORT
GetGpuMemoryBufferGUIDForTracing(uint64_t tracing_process_id,
    GpuMemoryBufferId buffer_id);

// This interface typically correspond to a type of shared memory that is also
// shared with the GPU. A GPU memory buffer can be written to directly by
// regular CPU code, but can also be read by the GPU.
class GFX_EXPORT GpuMemoryBuffer {
public:
    virtual ~GpuMemoryBuffer() { }

    // Maps each plane of the buffer into the client's address space so it can be
    // written to by the CPU. This call may block, for instance if the GPU needs
    // to finish accessing the buffer or if CPU caches need to be synchronized.
    // Returns false on failure.
    virtual bool Map() = 0;

    // Returns a pointer to the memory address of a plane. Buffer must have been
    // successfully mapped using a call to Map() before calling this function.
    virtual void* memory(size_t plane) = 0;

    // Unmaps the buffer. It's illegal to use any pointer returned by memory()
    // after this has been called.
    virtual void Unmap() = 0;

    // Returns true if the buffer is currently being read from by the system's
    // window server, and should not be written to.
    // TODO(ccameron): This is specific to the Mac OS WindowServer process, and
    // should be merged with synchronization mechanisms from other platforms, if
    // possible.
    virtual bool IsInUseByMacOSWindowServer() const;

    // Returns the size for the buffer.
    virtual Size GetSize() const = 0;

    // Returns the format for the buffer.
    virtual BufferFormat GetFormat() const = 0;

    // Fills the stride in bytes for each plane of the buffer. The stride of
    // plane K is stored at index K-1 of the |stride| array.
    virtual int stride(size_t plane) const = 0;

    // Returns a unique identifier associated with buffer.
    virtual GpuMemoryBufferId GetId() const = 0;

    // Returns a platform specific handle for this buffer.
    virtual GpuMemoryBufferHandle GetHandle() const = 0;

    // Type-checking downcast routine.
    virtual ClientBuffer AsClientBuffer() = 0;
};

} // namespace gfx

#endif // UI_GFX_GPU_MEMORY_BUFFER_H_
